The invention generally relates to semiconductor manufacturing and integrated circuits and, more particularly, to circuits and methods for providing electrostatic discharge protection.
An integrated circuit may be exposed to electrostatic discharge (ESD) events that can direct potentially large and damaging ESD currents to the integrated circuits of the chip. An ESD event involves an electrical discharge from a source, such as the human body or a metallic object, over a short duration and can deliver a large amount of current to the integrated circuit. Precautions may be taken to protect an integrated circuit from ESD events. One such precaution is to incorporate an ESD protection circuit into the chip. If an ESD event occurs, the ESD protection circuit triggers an ESD protection device, such as a silicon-controlled rectifier, to enter a low-impedance, conductive state that directs the ESD current to ground and away from the integrated circuit on the chip. The ESD protection device clamps the ESD protection device in its conductive state until the ESD current is drained and the ESD voltage is discharged to an acceptable level.
Circuits and methods are needed to provide improved electrostatic discharge protection.